*bump*Two books (recently purchased by me--long live AbeBooks and its Spanish equivalent Iberlibro!

) about the music scene in the 1950s:
Avec Stravinsky, ed.
Pierre Souvtchinsky, Ed. du Rocher, Monaco, 1958.
This book is discussed in vol. 2 of
Stephen Walsh's biography of
Stravinsky. It includes texts by the composer himself,
Robert Craft,
Pierre Boulez and
Karlheinz Stockhausen. Apparently, this
Avec Stravinsky was meant to publicize Stravinsky's then recent embracing of serialism.
and
La musique et ses problèmes contemporains 1953-1963. Julliard, Paris, 1963 (Collection "Cahiers Renaud - Barrault").
N.B.: I haven't been able to locate a cover image on the web (the image above is of the 1953 cahier, essentially the first half of the book I found).This publication unites the two numbers of the "Cahiers de la Compagnie Renaud - Barrault" decicated to the Domaine Musical, the first one from 1953, and then a second one for the 10th anniversary of that concert series. Texts by
Barrault, composers like
Boulez (of course),
Barraqué,
Kagel,
Berio,
Stockhausen et al., poets
Char and
Michaux, and assorted figures like
Heinrich Strobel,
André Schaeffner,
Souvtchinky,
Boris de Schloezer and
Adorno.